The Secret History of Iraq’s Invisible War

In the early years of the Iraq war, the U.S. military developed a technology so secret that soldiers would refuse to acknowledge its existence, and reporters mentioning the gear were promptly escorted out of the country. That equipment – a radio-frequency jammer – was upgraded several times, and eventually robbed the Iraq insurgency of its most potent weapon, the remote-controlled bomb. But the dark veil surrounding the jammers remained largely intact, even after the Pentagon bought more than 50,000 units at a cost of over $17 billion.

Recently, however, I received an unusual offer from ITT, the defense contractor which made the vast majority of those 50,000 jammers. Company executives were ready to discuss the jammer – its evolution, and its capabilities. They were finally able to retell the largely-hidden battles for the electromagnetic spectrum that raged, invisibly, as the insurgencies carried on. They were prepared to bring me into the R&D facility where company technicians were developing what could amount to the ultimate weapon of this electromagnetic war: a tool that offers the promise of not only jamming bombs, but finding them, interrupting GPS signals, eavesdropping on enemy communications, and disrupting drones, too. The first of the these machines begins field-testing next month.

On a fist-clenchingly cold winter morning, I took a train across the Hudson River to the secret jammer lab.

Tucked behind a Target and an Olive Garden knock-off, the flat, anonymous office building gives no hint of what’s inside. Nor do the blank, fluorescent-lit halls. But open a door off of one of those halls, and people start screaming.

“Screens off!” barks a man with a fullback’s build. “Turn off the test equipment!” On the ceiling, a yellow alarm light flashes and spins — the sign that someone without a security clearance is in a classified facility.

Afghan militants began attacking U.S. troops with improvised explosive devices in the first days after the October 2001 invasion. By early ’02, al-Qaida bomb-makers were cramming radio frequency receivers and simple digital signal decoders into the bases of Japan InstaLite fluorescent lamps. Then they’d connect the two-and-a-half inch wide lamp bases to firing circuits, and to Soviet-era munitions. The result was a crude, radio-controlled weapon dubbed the “Spider” by the Americans. With it, an attacker could wait for his prey, set off the bomb at just the right moment — and never have to worry about getting caught. When the explosion happened, he’d be hundreds of yards away.

Worse, U.S. forces had no way of blocking the Spider’s triggering signal. Military bomb squads carried around a few half-assed jammers. But they couldn’t be mounted on vehicles, “and they were too weak to provide protection beyond a few yards,” Rick Atkinson notes in his exquisite history, Left of Boom: The Struggle to Defeat Roadside Bombs.

‘If somebody sits a kilometer away with a radio and targets our guys, we’ve got no ability to get him.’

Navy engineers hustled to build something a little stronger, and a little more portable. By November of 2002, they had a jammer called Acorn that was hard-wired to stop Spiders. It wasn’t much. As a so-called “active jammer,” the Acorn put out a relatively-indiscriminate “barrage signal” that ate up power and generated all kinds of interference. That kept its effective radiated power — the amount of signal hitting any one bomb receiver — low. The signal was so weak, the jammer had to be left on and screaming constantly. Otherwise, troops would be inside the bomb’s danger radius before they ever had a chance to block it. Worse, it could only block the specific receivers used in Spiders. If the bombers switched frequencies, the countermeasure would be useless.

Meanwhile, the Army looked for ways to modify its Shortstop Electronic Protection System, designed to shield troops from artillery and mortar fire. This was a so-called “reactive” countermeasure. It monitored the airwaves, listening for one of the radio signals used by the munitions’ proximity fuses. Once the countermeasure heard that signal, Shortstop recorded it, modified it, and then blasted it back at the munition. By confusing the weapons with their own signals, Shortstop could fool the shells into prematurely detonating.

The soldiers tweaked the Shortstop to scan for radio-controlled bombs’ triggering frequencies, and to rely on a Humvee’s power supply. “The wife of one Fort Monmouth engineer collected miniature kitchen witches that inspired a new name for the device: Warlock Green,” Atkinson recounts.

Five Warlock Greens accompanied U.S. forces into Iraq in March, 2003. By mid-summer, there were 100 jammers in the warzone. It wasn’t nearly enough. Iraq’s militants had learned from their compatriots in Afghanistan, and were setting off remotely-detonated explosives everywhere.

Just like the first turn of this improvised explosive device (IED) war, the electronic countermeasures were having trouble keeping up with the bombs. It took Warlock Green, ultimately manufactured by the EDO Corporation, a couple of seconds to record, modify, and rebroadcast a triggering signal. An insurgent bomber could set off an explosive in a few fractions of a second, if he had a simple, low-powered trigger, like a garage door opener. The jammer didn’t have time to catch up.

The jammers could only cover a small slice of the radio frequency spectrum. Whenever the insurgents should change triggers — from say, door openers to key fobs — the jammer-makers would have to go back to the drawing board. Warlock Greens could be reprogrammed, within limits. The Acorns couldn’t; the new threats rendered them useless.

“Every time we put a countermeasure in the field – especially with Warlock – they were able to outstrip it,” says Paul Mueller, a long-time defense executive, who supervised jammer-building operations at EDO and at the ITT Corporation. “They were a step ahead of us.”

‘Every time we used a countermeasure, they were able to outstrip it.’

But with insurgents setting off 50 IEDs a week, even the step-behind jammers were better than no jammers at all. By May 1, 2004 — one year to the day since President George W. Bush declared the end of major combat operations — the improvised bombs had wounded more than 2,000 American troops in Iraq. The IEDs killed 57 servicemembers in April alone, and injured another 691. “IEDs are my number-one threat in Iraq. I want a full-court press on IEDs,” Gen. John Abizaid, then the top military commander in the Middle East, wrote in a June 2004 memo.

In the early fall of 2004, the Army signed a contract for 1,000 Warlocks. By March, 2005, the Army upped that order to 8,000 jammers. It was a high-tech, electromagnetic surge. And it was meant to send the militants sliding back down the scale of sophistication. “If somebody can sit a click [kilometer] away with a radio and target our guys, we’ve got almost no ability to get him,” says a source familiar with the jammer buildup. “But if he’s doing the Wile E. Coyote thing, and pushing down that plunger, at least we’ve got some chance to shoot him before he gets it down.”

All the big defense contractors — and lots of little ones — got into the electronic countermeasure business. The Marines bought one model; the Army another; Special Operations Forces, a third. The Army began buying Warlock Reds — small, active jammers that blocked out the low-powered triggers that Warlock Green couldn’t stop in time. Warlock Blue was a wearable jammer, to protect the infantryman on patrol. Each countermeasure had its shortcomings; Warlock Blue, for instance, was “a half-watt jammer at a time when some engineers suspected that 50 watts might be too weak,” Atkinson notes. But no commander could afford to wait for a perfect, common bomb-stopper; too many men were getting blown up. By May 1, 2005, the number of U.S. troops wounded by the bombs had climbed to more than 7,700.

There were drawbacks to throwing all those countermeasures into the field at once. Warlock Green would sometimes mistake Warlock Red’s signal for an enemy’s, and go after it. That would lock the jammers in a so-called “deadly embrace,” cancelling one another out.

When the Warlocks were operational, they wreaked havoc with both the remote-controlled robots that were supposed to handle bombs at a safe distance and the radios soldiers used to warn each other about upcoming threats. Warlock Red “prevented communications” from three of the Army’s most common radio systems, according to a classified report released by WikiLeaks. The report recommended keeping radios and countermeasures in different vehicles to prevent the “electronic fratricide.” Of course, that meant a soldier with a jammer in his Humvee was cut off from the rest of his convoy.

For reporters, pointing out these drawbacks — in fact, pointing out anything about the jammers — risked a swift military response. In Baghdad, a top official with the Joint IED Task Force called me an al-Qaida ally for putting together a Wired.com report on counter-IED technologies based on other publicly-available information. A few months later, David Axe mentioned the Warlocks in a post for Defensetech.org from Iraq. Shortly after the post went live, Axe was detained, and was promptly thrown out of the country.

Even more secret were the flights of the jammers in the sky. The Navy’s EA-6 Prowlers could not only block triggering signals; they could remotely detonate the bombs, as well. But they had to be very, very careful. U.S. vehicles equipped with jammers had to get off of the roads, or risk the deadliest embrace of all. Pilots had to make sure that civilians were nowhere nearby, when they set the bombs off.

In July of 2005, I found myself at a rubble-strewn intersection of two highways, not far from Iraq’s Abu Ghraib prison. The Explosive Ordnance Disposal team I was traveling with called this place the “Death X,” because of all the attacks nearby. The bomb squad was called out to the area because of a suspicious package — a package that turned out to be nothing more than a balled-up pair of pants. But on the way back from the incident, our Humvee rolled over an artillery shell, buried in the highway’s middle lane and wired to a radio. An improvised bomb.

The IED didn’t go off, for reasons that weren’t completely clear. The Death X bomber might have gotten cold feet. More likely, one of Warlocks in the Humvee prevented him from detonating the weapon.

That same day, I took a Black Hawk ride to the town of Mahmudiya, just south of Baghdad. At the outpost there, I met Staff Sgt. Johnnie Mason (pictured), who showed off the cordless phone than nearly killed him. It was wired to a series of artillery shells, and stuffed under a row of human corpses, rotting by a canal in the 118 degree heat.

The dead bodies, they smelled like catfish bait.

When Mason — a lanky, 31 year-old Texan with big brown eyes and a goofy smile — came across the bomb, he wanted to puke into his Kevlar protective suit. The dead bodies, they smelled like catfish bait. But there was no time to heave. Mason knew the weapon was live, and that he was outside his Warlock’s protective bubble. He figured he only had a moment or two to act before a bomber remotely detonated his device. So Mason jumped behind a three-foot berm, and crouched into a fetal position before the shock wave hit him. “It was too fast for me to think, ‘Oh God, I’m gonna die,'” Mason said. “It was just instant fear.”

The bomb was less than twenty feet away when it went off. Dirt flew up. Shards of bomb zipped through the air. The shockwave knocked Mason over. But he was intact, somehow.

Mason sat down for fifteen minutes, drank some water. And then he went right back to the bodies. Before the explosion, he noticed a second shell, 20 meters away. So Mason took a couple pounds of C4 plastic explosive to demolish the thing. “I still had a job to do,” he told me.

Five months later, on the 19th of December, Mason found himself on another highway, responding to another suspicious package call. His team stumbled on another IED, practically beneath their feet. Insurgents were routinely luring bomb squads with one weapon in an attempt to kill them with the second. In this case, the tactic worked.

Mason told everyone to clear out of the way while he tried to disarm the device. Then the bomb went off.

Militant bombmakers increasingly turned to long range cordless telephones and cell phones for their triggers. That was a serious issue. The digital devices were built to overcome dropped packets, reflected signals, and transmission errors. Warlock Green’s trick of fooling a trigger with its own, modified signal didn’t work. The gadgets were used to the hiccups.

The ‘deadly embrace’ between the jammers began to loosen.

Behind the scenes, however, there were signs of improvement. The Navy sent to Iraq hundreds of electronic warfare specialists, to bring the cacophony produced by 14 kinds of jammers into some sort of harmony. Protocols were established, to allow one device to send its signal and then go silent for a few milliseconds, so another gadget could broadcast; that allowed Warlock Red and Warlock Green to be packaged into a single, combination unit. The ‘deadly embrace’ between the jammers began to loosen. The Pentagon’s IED task force became the Joint IED Defeat Organization, or JIEDDO, with a $3.6 billion annual budget to tame the homemade bomb threat. Mongtomery Meigs, the retired four-star general in charge of the organization, worked to unravel the bureaucratic tangle that tied up bomb trigger analysis. The intelligence specialists at the Combined Explosive Exploitation Cells got faster and faster at analyzing which frequencies the insurgents were using. That, in turn, allowed the jammers to be updated more quickly, so they could counter emerging threats.

Most importantly, perhaps, a new generation of jammers entered the battlefield, thanks to JIEDDO’s billions. Some, like the Marines’ Chameleon countermeasure, could cover a broad range of frequencies, from low-powered triggers (like key fobs) to high-powered ones (like walkie-talkies). In February of ’06, the Corps announced they were buying 4,000 of the 125-pound, Humvee-mounted systems.

Warlock Duke used a technique called “set-on” jamming to overcome the more advanced digital triggers. Like Green, Duke would listen for a malicious signal. But rather than confuse a receiver with a modified version of its own signal, Duke had a series of built-in jamming responses, designed to fool very specific devices. If Duke heard a particular FM walkie-talkie, Duke would send out a specific FM spoof. It was actually a cruder technique than Green’s. And it relied on very detailed knowledge about exactly which threats were in which area. But it worked. Tens of thousands were eventually fielded. And slowly, slowly, the percentage of radio-controlled bombs as a whole began to fall. Then they began to disappear altogether.

“Electronic warfare defensive systems were instrumental in saving thousands of Soldiers and Marines from being casualties in Iraq,” emails retired Lt. Gen. Michael Oates, who led the 10th Mountain Division during its tour in Iraq at the time, and then became director of JIEDDO. “The high use of remote controlled detonation capability… was a significant and effective threat until the jammers were developed.”

By the time I returned to Iraq, in the summer of 2007, IEDs had become relics in broad swaths of the country. The insurgents had largely abandoned their tool of choice.

It was not altogether good news.

North of Baghdad, insurgents took insulated copper threads, some not much thicker than a hair, and buried them in the dust. Then they strung them out for as long as a kilometer. At one end was an insurgent triggerman. At the other, an explosively formed projectile. It was a crude approach to killing — even more primitive than those first bombs planted in Afghanistan. But it was lethally effective.

These “command wire” bombs had a fatal flaw, however. Insurgents had to stick around to set them off. That made them vulnerable to American counter-attacks and preemption. And that brought the number of bombs and bomb fatalities way down. In December of 2007, only nine U.S. troops were killed by IEDs, and another 166 were wounded. It was still an awful toll. But it was a tiny fraction of the 69 slain and 473 injured in December of 2006.

All the gadgets built for Iraq were worthless against Afghanistan’s throwback threats.

The casualty figures continued to fall as the military began to field a third generation countermeasure — one that could stomp out a huge swath of radio triggers with all sorts of jamming techniques. In April of 2007, the Pentagon signed a deal with EDO for up to 10,000 of the so-called “CVRJs.” Shortly thereafter, ITT bought EDO, and began to crank out the machines. The CVRJ held up to 15 mission loads at once, quadrupled the number of simultaneous channels it could jam on, and doubled the spectral coverage of pre-existing systems. More importantly, the CVRJ could be reprogrammed on the fly: not just the frequencies it covered, but the specific responses it used to counter particular threats. “For the first time ever,” says Mueller, the EDO-turned-ITT executive, “we had a canvas to create a painting.”

That enabled CVRJ to target the most advanced triggers — the ones which relied on the latest mobile and long-range cordless phones. The new phones hopped between frequencies and spread their signal across the spectrum to overcome interference. That made them much harder to jam. But the phones have a potential flaw. They relied on software protocols to establish connections between transmitter and receiver. Those protocols could be spoofed, keeping the connection from ever happening. That is, if you had a fully programmable countermeasure, like CVRJ.

In the broadest sense, the strategy behind the U.S. jammer buildup had succeeded. Thanks to the Americans’ bleeding edge technologies, the militants had dropped back down the ladder of sophistication. They were now taking the Wile E. Coyote approach — pushing down the plunger to detonate the bomb — and suffering for it. “That was the whole intent of the program: pushing the enemy back to archaic means,” says a source familiar with the effort. “So they’d actually have to face you and fight you.”

In Afghanistan, however, the terrain favored the low tech. All the gadgets the Americans had bought and built for Iraq proved largely worthless against a new slew of throwback threats. The bombs were largely made of wood and fertilizer, making them practically invisible to metal detectors. No command wires were needed to set them off; just the pressure of an unlucky boot. The placement of the bombs added to their effectiveness. The U.S. military’s new hard-shelled, blast-deflecting vehicles were built for Iraq’s well-paved roads. So the insurgents put their explosives in the gullies and the mud paths, where the trucks were useless. The bomb-handling robots couldn’t handle the rough terrain, either. And, during the summer, the weather was so hot, EOD technicians didn’t even bother wearing their protective suits.

As the fighting grew more intense — and the U.S.-led coalition poured more troops into the Afghan campaign — the total number of bombs there crept up, from 1,931 in 2006 to 3,276 in 2008. By July, 2010, that figure had reached nearly 1,400 explosives found or detonated a month. It’s stayed about that high ever since.

The deaths and injuries caused by these bombs continued to mount, as well. In July 2008, 25 American troops were wounded by Afghan IEDs. In July 2009, that figure was 174. In July 2010, the number was 378 injured — about 15 times higher than the casualty count from two years before.

JIEDDO shifted its focus to compensate. Jammers alone weren’t going to do much against these no-tech weapons. The organization spent more on surveillance and intelligence analysts, trying to find ways to crack apart Afghanistan’s IED networks.

But even if those networks are shredded tomorrow, there’s a sense in the Pentagon that the improvised bomb has now become a permanent threat. Over the last six months, there’s been an average of 245 jury-rigged explosives found or detonated — outside of Iraq and Afghanistan. The IED has gone global.

The lab where ITT engineers work on the fifth generation of bomb-stoppers looks like a schoolroom — from the desks facing the front of the room to the guy with the ponytail and circular glasses delivering the lecture. Behind the guy — he’s an engineer, not an English prof — are two screens. One shows a CGI version of a jammer’s guts: the amplifiers, the transceivers, what have you. The other screen shows a map of a military base, covered in red and green. It shows how the countermeasure might perform with that configuration.

The Pentagon can’t afford any more to crank out yet another stop-gap countermeasure for yet another kind of bomb. So the military is instead backing the development of a jammer that can be used anywhere, and for years to come. The system is awkwardly known as Joint Counter Radio-Controlled Improvised Explosive Device Electronic Warfare 3.3. An initial batch of 21 of these JCREW machines are supposed to ship to the military in July for field testing. If it passes those trials, among other hurdles, up to 20,000 of the uber jammers could eventually be built.

‘Aircraft, vehicles, ships, and troops’ are all on the new jammer’s target list.

But before it gets into troops’ hands, the countermeasure gets simulated here. Lower the antenna from 15 feet to five makes more red splotches appear on the map, indicating gaps in jammer coverage. Add a bigger amplifier, and some of the red goes away.

ITT has bigger ambitions for its JCREW machine than simple bomb-blocking. Step through a door, and there’s a more traditional-looking electronics workroom: cable-strewn benches, and machines stacked head-high. Guys with soldering irons connect wires to boxey machines. The goal here isn’t to see how the countermeasures block signals. It’s to see how they talk to one another. There’s a JCREW jammer designed for vehicles, another for individual troops, and a third to protect bases. All of the machines are meant to work together.

The JCREW 3.3s are supposed to be fully networkable, and able to communicate over the military’s wireless battlefield networks. That should save them some power and interference– if you’ve got four jammers in a convoy, for instance, one can silence a receiver while the other three quiet down. Or maybe that jammer can spot the threat, record its signal and location, and transmit that information back to headquarters. In that way, the new machine becomes more than a single bomb-beater. The system might help track down the explosives, and the guys who planted them. It could be configured to listen in on communications — those cell phones are for more than triggering explosives, after all. Hell, if the machines are passing data back and forth, they could work as radios themselves, in theory.

With proper power management and frequency coordination, the new JCREW could have a whole new range of “potential targets,” according to a company briefing. Those include “information systems and infrastructure,” drones, communications grids, sensors, “position, navigation and timing capabilities” (that’s shorthand for GPS signals), as well as “aircraft, vehicles, ships, troops.” In other words: everything.

For now, these are just ideas, not orders. “It’s all on the roadmap, potentially,” Mueller says. “How much we actually do remains to be seen.”

But one thing is for sure: it’s a long way from stopping crude triggers, stuffed into disposable lamps. It’s a long way from frantically tweaking electronics in the hope of somehow keeping thirty soldiers a day from being blown up. It’s a long way from the near decade-long fight against remote-controlled bombs in which the enemy had the advantage of being the first mover. This may be the chance to get ahead, before the next wave of terror weapons hits.